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La base molecular para la inversión de la quiralidad supramolecular promovida por el agua en los nanotubos de roseta

Ross S Johnson¹, Takeshi Yamazaki, Andriy Kovalenko

¹National Institute for Nanotechnology, Department of Chemistry, University of Alberta, 11421 Saskatchewan Drive, Edmonton, Alberta, Canada.

Journal of the American Chemical Society

|April 10, 2007

Resumen

Los motivos de GwedgeC quirales forman nanotubos de roseta helicoidales (RNTs) que invierten su quiralidad de imagen especular con trazas de agua. Esta inversión de quiralidad supramolecular está controlada termodinámicamente y conduce a nanoestructuras quirales estables.

Área de la Ciencia:

Se trata de una química supramolecular.
Nanotecnología La nanotecnología es la nanotecnología.
Biología química Biología química.

Sus antecedentes:

Los nanotubos de roseta helicoidal (RNT) se autoensamblan a partir de motivos GwedgeC, análogos de bases de ADN con enlaces de hidrógeno de guanina y citosina.
La quiralidad de los RNTs surge de la estructura del motivo GwedgeC y el proceso de autoensamblaje.
Los motivos de GwedgeC quirales generalmente favorecen la formación de una RNT quiral específica.

Objetivo del estudio:

Para sintetizar y caracterizar un motivo quiral GwedgeC.
Para investigar el comportamiento de autoensamblaje de este motivo en diferentes disolventes.
Comprender el mecanismo de la inversión de la quiralidad supramolecular inducida por el agua.

Principales métodos:

Síntesis y caracterización de un motivo quiral de GwedgeC.
Estudios de autoensamblaje en metanol y diferentes concentraciones de agua.
Técnicas de caracterización física (por ejemplo, espectroscopia, microscopia).
Modelado computacional para dilucidar el mecanismo de autoensamblaje.

Principales resultados:

El motivo quiral GwedgeC se autoensambla en RNT helicoidales en el metanol.
La adición de pequeñas cantidades de agua (<1% v/v) desencadena la inversión de la quiralidad supramolecular de la imagen especular, formando "quirómeros" estables.
La inversión de quiralidad resulta del autoensamblaje termodinámico (agua) y cinético (metanol) de los isómeros conformacionales.
Los quirómeros exhiben una quiralidad estable, comportamiento dominante / recesivo, memoria de quiralidad, amplificación y transferencia catalítica.

Conclusiones:

Se propone un mecanismo para la inversión de la quiralidad supramolecular desencadenada por el agua en los RNT basados en GwedgeC.
El estudio demuestra el control de la quiralidad supramolecular a través de interacciones con disolventes.
Los hallazgos destacan el potencial de los motivos GwedgeC para crear nanomateriales sensibles y quirales.

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